The triquetra has been found on runestones in Northern Europe and on early Germanic coins. It presumably had pagan religious meaning and it bears a resemblance to the Valknut, a symbol associated with Odin.
G Scale Trains are usually referred to as Garden Trains since they are the largest of the model trains and are used outdoors as well as indoors.
The toy train market evolved into scale modeling and Lionel's prized 700e Hudson was cataloged in O-gauge starting in 1937 as their top of the line train. The large size of Standard Gauge no longer symbolized top of the line Lionel.